Flexible coupling



July8, 1947. I J. N. WOLFRAM I 2,423,745

FLEXIBLE COUPLING Filed Nov. 22, 1944 v Z2 /8 J I I I v I v 4 2 Patented July 8, 1947 FLEXIBLE COUPLING John N. Wolfram, Cleveland, Ohio, assignor to The Parker Appliance Company, Cleveland, Ohio, a corporation of Ohio Application November 22, 1944, Serial No. 564,578

1 Claim.

Th presentinvention relates to tube cou-.

plings, and more particularly to improvements in couplings for flexibly clamping the end of a metal tube.

An important object of the invention resides in the provision of a flexible coupling for tubes or the like including threadedly engaged body and nut members defining therebetween an annular chamber for an annulus of rubber or like material, and a metal sleeve surrounding the rubber annulus for limiting the amount of deformation of the same when the nut and body are in coupled relation.

Another object of the invention is to provide a coupling of the above character wherein the rubber annulus is formed so as to minimize pinching and extrusion as the nut is moved relative to the body member.

A further object of the invention is to provide a coupling of the above character wherein accidental detachment of the tube is resisted through engagement of the nut and sleeve;

The above and other objects of the invention will in part be obvious and will be hereinafter more fully pointed out.

In the accompanying drawings,

Figure 1 is a longitudinal view in section, showing the coupling with the tube inserted therein before the coupling members have been tightened relative to one another.

Figure 2 is a similar view in section illustrating th flexible coupling after the coupling members have been tightened relative to one another.

Referring to th drawing for a more detailed description thereof, the new and improved flexible coupling is generally designated by the reference numeral 5 and includes a body member 6, and nut I, which threadedly engage one another, as at 8. The other end of the body member is provided with an exteriorly threaded portion 9 for attachment ,to a member, not shown,with which the tube is to be coupled. The body member 6 is provided with a central bore III and counterbore II communicating therewith. The diameter of the central bore It! is substantially equal to the diameter of the tube I2; being coupled by the body member and nut. tube I2 is shown formed with an outwardly flared portion I3, it is to be understood that this end of the tube can be formed with a bead or any other type of enlargement within the meaning I of th present invention. It is evident, however, that the enlarged end of the tub I2 is received within the counterbore II and is normally spaced from the walls thereof.

The nut l and body member 6, when in threaded engagement, including the counterbored area of the latter, define an annular chamber I4 in which is disposed a packing member I5 in the While the form of an annulus of rubber or like material, said packing member surrounding the tube I2 in the region of the enlarged or flared end I3 thereof. This packing member I5 can be of the shape shown, or if desired, it can be of elliptical or circular cross section. In the form illustrated, the edges are tapered as indicated at I6 and I1, defining spaces in which the material is extruded when the nut is tightened on the body member a shown in Figure 2.

The coupling further includes a metal sleeve I8 which surrounds the packing member I5, and which is formed with an inwardly turned flange I9 providing a side wall for one end of said packing member. When the coupling members are in their initially assembled relation shown in Figure 1, the flange I9 abuts the end of the body member 6, and at the same time contacts the tube I2 in the region of the flared end I3. There is, however, a slight clearance between the flange I9 and tube I2 in order to minimize extrusion of the rubber packing into the coupling at the area designated 20 and to also provide for full floating of the tube in rubber to effectively resist vibration and/ or flexing of the tube.

The position of the tube I2 and the coupling members before the coupling members are tightened relative to one another is shown in Figure 1. When the nut I is turned on the threads 8 relative to the body member 6, the packing member IB will be deformed so as to entirely fill that portion of the annular chamber defined by the flange I9 and inturned end 2i of the nut I. As soon as the inturned end 2I makes contact with the end 22 of the sleeve I 8, it will be a signal indicating that the coupling has been'properly tightened. Also, the extent of deformation of the packing material I8 will be limited by the metal to metal engagement of the nut and sleeveat 23. When the coupling members are finally tightened, the parts will assume the positions shown in Figure 2.

The coupling, as thus formed, prevents leakage by the metal to metal seal between the sleeve and body at 24 and a rubber seal between the sleeve and tube at 25, and also at any one of the surfaces 26, 21 or 28. Under severe pull out strains, the "enlarged end of the tube, whether,

it be flared or beaded, will engage the smoothly rounded edge 29 of the sleeve flange I9, thereby preventing cutting'in and wearing or abrasion, which would tend to weaken the coupled parts. Displacement of the tube from the coupling is positively resisted through engagement of the nut and sleeve at 23.

It is to be clearly understood that various changes in the details and construction and arrangement of parts may be made without departingfrom the scope of the invention as set forth in the appended claim.

1 claim:

A flexible coupling for a tube having an enlar'ged end, comprising coupling members having threaded engagement with each other for housing the enlarged end of a tube, said coupling members defining therebetween an annular chamber, apacking member disposed within said annular chamber and surrounding said tube in the region of the enlarged end, and a sleeve surrounding said packing member and having an inwardly extending flange at one end in contact with the tube adjacent the enlarged end thereof and abutting against one of the coupling members, the other end of said sleeve abutting against the other coupling member upon relative movement of said coupling members toward one another to tightly press the packing against the tube adjacent the enlarged end whereby said 4 v I tube'is resiliently supported in said coupling and positively restrained from withdrawal therefrom.

JOHN N. WOLFRAM. 

